It is one of my pet peeves, too. Not only are the costumes wrong, but quite often the hairstyles and facial hair are anachronistic as well. What really bugs me is when they have the men dressed in, say, mid-19th century costumes but the women are wearing 1890s dresses, as if the characters were living in different decades.
I have memories of my grandmother and her younger sister, both women in their 50s at the time, working flatblade D-handle shovels to get the oats from the wagon to the silo.
They were doing the same work they'd seen their mother and her sisters do, and were wearing the same clothes ~ and heavy work gloves.
That was life in the Midwest.
It is the movies for goodness sake. If you want authenticity go to a museum
Zippers! My pet peeve is zippers or incorrect corsetting. LOL My husband leaned over to me during The Young Victoria and said, “WOW, no comment on the zippers?” LOL I was too awestruck by the baseboard heaters in the scene where they were discussing how cold the castle was and whose responsibility it should be to lay the fires.